Resistant-surface alloy of iron



45 under,

Patented Sept. 1, 1925.

1,551,931 PATEN T. 5OFFICE.

GE OR GE H. CHARLS, OF CANTO'N, OHIO, ASSIGNOR TO UNITED ALLOY STEEL CORPORA- TION, F CANTON, OHIO, A CORPORATION OF NEW YORK.

RESISTANT-SURFACE ALLOY OF IRON.

No Drawing.

To all whom it may concern:

Be it known that I, GEORGE H. CHARLB, a citizen of the United States, and a resident of Canton, Stark County, State of Ohio, have invented an Improvement 'in Resistant-Surface Alloys of Iron, of which the following is a specification.

his invention relates to alloys of iron. One of the objects of this invention is to 1 provide a simple and yet practical alloy of iron, the surface of which will remain bright and uncorroded during long and severe use. Another object is to provide an alloy of the above nature which may be readily and cheaply manufactured and worked. Other objects will be in part obvious and in part pointed out hereinafter.

The invention accordingly consists in the ideas, features and combinations of elements illustratively herein described, and the scope of the application of which is indicated in the appended claims.

Prior to describing this invention in detail, it is to be noted that the term iron alloy is used in a broad sense to include alloys in which carbon may or may not be present according as it is or is notspecified, and thus to take in what might be specifically termed a steel alloy. It is 39 also to be understood resistant-surface as used herein denotes that quality of the alloy by virtue of which it is so constituted that it is adapted to present throughout its entire mass a surface which will maintain its original character in the face of heat or any other agencies tending to corrode or discolor it.

As an illustrative embodiment of this invention which I have found to give excellent results, I employ chromium from 16.0% to 25.0% and molybdenum from 05% to -.12%.

The carbon is preferably kept low by which I- mean,

in this connection, 20% or and I have found excellent results with carbon in a range of from .03% to .07

Such elements as commonly present 59 and steel, are keptas low as possible.

The molybdenum is also preferably kept low, for it attains its maximum elliciency in a very small amount.

However, a considerable deviation may be made from the above-specified ranges in all commercial iron that the expression phosphorus and sulphur,

Application filed April 14, 1924. Serial No. 706,568.

without loss of beneficial results from this invention, and accordingly in certain of the claims broader ranges of the constituent elements are specified by setting limiting percentages higher or lower than those of 60 the preferred range hereinbefore set forth.

It is to be understood, however, that it is applicants present belief that as the narrower ranges are preferable to the broader ranges, intermediate ranges as specified in certain of the claims are also preferable to the broader ranges as they more closely approximate applicants preferred embodiment.

I prefer to add vanadium in j a small amount, as from .10% to .5 0%, which acts as a scavenger and enables the remaining elements to coact more efficiently.

It is to be understood that all of the alloying elements are so added as to uniformly distribute themselves throughout the mass of the metal.

An alloy such as is above set forth will be found to attain the objects of this inventionand, among others, the advantages herein set forth. It will be found, furthermore, that the desired surface and other characteristics may be gained without special heat treatmen As many variations might be made in the above illustrative embodiment of this invention, it will be understood that all mat- ,ter herein set forth is to be interpreted as illustrative and not in alimiting sense.

I'claim as my invention:

1. A resistant-surface alloy of iron containing as the principal elements, in combination with the iron, molybdenum from 05% to 20%, chromium from 3.0% to 25.0%, and carbon in an effective amount not exceeding 20%.

A resistant-surface alloy of iron containing as the principal elements, in combination'with the iron, molybdenum from i .05% to 20%, chromium from 16.0% to 25.0%, and carbon in an effective amount not exceeding 20%.

3. A resistant-surface alloy of iron-containing as the principal elements, in combination with the iron, molybdenum from 05% to 12%, chromium from 3.0% to 25.0%, and carbon in an effective amountnot exceeding 20%.

i. A resistant-surface alloy of iron containing as the principal elements, in combination with the iron, molybdenum from .05% to 420%, chromium from 16.0% to 25.0%, and carbon in an effective amount not exceeding 10%. v

5. A resistant-surface alloy of iron containing as the principal elements, in combination with the iron, molybdenum. from .05% to 12%, chromium from 16.0% to 20.0%, and carbon from .03,% to .07

6. A resistant-surface alloy of iron conta-ining as the principal elements in combination with the iron, chromium from 3.0% to 30.0%, molybdenum in an effective amount, and vanadium in an appreciable amount not exceeding .50%.

In testimony whereof, I have signed my name to this specification this third day of April, 1924;.

GEORGE H. CHARLS. 

